Operating mechanism for brakes



Feb. 27, 1923.

W. R. R. HISCUTT OPERATING MECHANISM FOR BRAKES shets--sheet 1 Filed Oct. 11,

mm; All

[NVENTUR WILLIAM ROBERT Em: HISCUTT.

PER. )Z

' ORNEYS,

Feb. 27, 1923.

W. R. R, HHSCUTT OPERATING MECHANISM FOR BRAKES Filed Oct. 11, 1921 2 sheets-sheet 2 War:- /@a M Fatented Fete. 27, I923 UNITED STATES (@FFHQEQ WILLIAM ROBERT HYDE HISCUTT, OF LONDON, ENG-LAND.

OPERATING MECHANISM FOR BRAKES.

Application filed October 11, 1921. serial No. scans.

To all whom it may concern: 4 the invention applied to the brake actuating Be it known that I, WILLIAM ROBERT RYDE shaft of a motor vehicle. In the draw- HIsoU'rr, subject of the King of Great Britings 55 ain and Ireland, and resident of 27 Harley Figure 1 is a plan View in elevation of the Mews North, Harley Street, London, in the brake actuating shaft and mechanism for county of London, England, have invented operating the same.

certain new and useful Improvements in Op- Figure 2 is a vertical longitudinal section crating Mechanism for Brakes, of which the through the brake actuating shaft. to following is a specification. Figure 3 is a side elevation and w My invention relates to improvements in Figure 4 is a front elevation of one of the operating mechanism for brakes and like sleeves mounted on the brake actuating and has for its object to provide a simple shaft. and effective mechanism which will auto- Fig. 5 is an end view of the apparatus. 65 matically adjust itself so as to take up wear Fig. 6 is a sectional end view showing the or slack when this exceeds a certain degree, toggles and cam.

in such a manner that the brake actuating JIhe actuating shaft a for the brake carlever or the like will always be maintained ries at one end a cam b or toggle or the like in substantially the correct position for apmechanism for operating the brake shoes, 70 plying the actuating force to the brake or blocks or their equivalent as will be readily my the like in the most efficient manner. understood. The shaft a extends through According to the general principle of the a bearing a formed integrally with the oesinvention, I arrange the operating lever for ing 0 of thelorake and at its opposite end is the brake or the like upon the shaft c'arryfu th supported i a b i 1 hi h may 75 ing the actuatin cam toggle or other mechbe rri d b n am or b k t; fi d t th anism, and hereinafter called the brake 3C- casing of the rear axle as hown diagramtuating shaft, 50 as to be capable of rotatgi ll i Fi 1 bearing. 1"i ing thereon. Between the Operaing l v the brake casing is provided on its outer face and a fixed abutment upon the brake casing ith a transverse l t' keyway i hi h so or other part is provided two sets of opp-oengages a. key or tongue f carried at one end so sitely inclined ratchet teeth, the separate in of a, ring or sleeve 9 mounted upon the nor members which carry the in r teeth brake actuating shaft a so that the shaft of the two sets of ratchets being inter-concan rotate therein. The sleeve 9 is pronected by a tongue and slot of such a size vided with ratchet teeth 9 on its opposite as to allow relative movement between them *face which cooperate with ratchet teeth h 35 to an extent sufiicient to allow clearance beon the adjacent face of a second sleeve or tween brake shoes and brake drum when ring n also mounted upon th h ft 0 S0 lever returns to 0d position after adjus that the shaft can rotate therein. The sleeve ment. it is formed at its opposite end with a. trans- The oppositely inclined ratchet teeth (20- verse slot or the like 7L into which engage- 41) operate to automatically adjust the position tongu k upon a member 70' keyed upon the 0f the brake actuating shaft to take up brake haft a and fixed by means of 9, taper wear or slack of the brake shoes or their pin or the like 70 or by other suitable means. equivalent. The brake actuating shaft also The tongues 0 upon this latter member are $95 carries a rod or bar which is connected by of less width than the slots 71 in the sleeve 45 a 5 ring to a-stationary portion of the veit with which the engage, and the diflerhie e for instance theback axle casing, in once in width of t e slot and tongue is such the case of a motor vehicle, and serves as an as to allow suflicient radial clearance beindicator as to. the extent of wear of the tween them to ensure the brake bein out of 1m brake shoes or the like. action when the brake operating ever at In order that the invention may be readily which is mounted on. the shaft (2 so that it understood reference is made to the accom can rotate therein is returned to normal po panying drawings, in which I have shown sition after adjustment;

The inner faces of the sleeve h and the member is are recessed to form an annular groove in which is located a coil spring m serving to press the two members apart, thus retaining the ratchet teeth 72, on the loose sleeve h engaged with ratchet teeth 9 upon the'ring g connected to the brake casing. The outer face of the member 7a fixed to the actuating shaft is provided with ratchet teeth k of an opposite hand which cooperate with similar ratchet teeth n formed on the adjacent face of the brake actuating lever n loosely threaded upon the shaft a. The actuating lever n is normally pressed towards the member is by a spring 8 located in an annular recess n and bearing against the inner face of the bearing d. The actuating shaft'a is secured against axial movement by a washer and nut p, 9 respectively, the nut screwing on to the end of the shaft and being locked in position by a split pin or other means.

The Washer p is fixed to the shaft by a small dowel pin w or other means and is preferably formed integrally with or is secured with any suitable manner to a lever or the like t which is preferably connected by means ofra coil spring 00 to a fixed por tion of the frame, or to the rear axle casing, said spring serving to help return the brake actuating shaft to its normal position. when the, said shaft is not being operated by the lever n.

The operation of the mechanism is as follows When the brake pedal or lever is operated to apply the brake. the operating lever n upon the brake actuating shaft a Will be partially rotated. and through the engage-- ment of the ratchet teeth a upon its face, it will also rotate the member which is fixed to theshaft a and will thus actuate the brake. If and when the amount of move ment or the extent of rotation of the shaft a necessary to actuate 'the brake, is greater than the difference between the width of the tongue 70 and slots 72 forming the connection between the fixed member 7c and the loose sleeve h it will cause the loose sleeve to be rotated to the extent of the excess movement of the shaft a.

It will thus be seen that the shaft a will be rotated through a predetermined distance without imparting corresponding movement to the sleeve 71,. For instance if the difference in width of the slots 7L2 and tongues 70 represents 10 degrees, the pitch of the ratchet also being 10 degrees. and it is found to effectively actuate the brake it isnecessary to rotate the shaft through 20 degrees, the engagement of the tongues it with the slots 71 will cause the sleeve h to be rotated to the extent of 10 degrees, The sleeve during this movement is mo ed axially against the action of the spring m and the ratchet teeth raaeyroa h ride over the ratchet teeth g on the stationary member 9. On the brake operating lever n being released, the memberilc fixed to the shaft (1 will rotate in the opposite direction independently of the sleeve IL through a distance representing 10 degrees and during a further distance 0f 10 de-' grees, the brake operating lever will bemoved axially against the action of the spring or, the ratchet teeth a sliding over the teeth is it being understood that the brake operating lever n is always returned to the predetermined position by a spring or the like connecting brake lever 12 with a fixed portion of the frame or back axle casing. By this means it will be seen that the actuating shaft a will always be automatically set to the correct posit-ion for the proper actuation of the brake for a given predetermined pressure or movement of the brake pedal lever, thus permitting braking to be efiected at all times independently of'wear of the brake shoes or the brake drum. It will be understood that the difference in width. of the slots k and the tongue k is such as to leave sufficient clearance to ensure the brake being out of' ac-tion when the operating lever or pedal is returned to its normal position.

The lever t which is fixed to the brake actuating shaft is preferably located so that it projects therefrom at right angles to a plane passing through the actuating cam 71 at the opposite end. By this means it is possible to ascertain at any time. whether the brake shoes or their equivalent require renewing or whether the extent of wear of the lining of the brake drum requires attention. For instance if the plane-passing through the cam Z) is normally horizontal when the brake is ofl'. the lever 25 will be substantially vertical and if, after a period of time owing to the brake shoes' or the brake drum becoming worn. it is found that this lever is inclined, say at 45 degrees. it will be at once obvious that the cam 72 is also inclined at the same angle to the horizontal, when the brake is off so that it will be at once seen that the, brake linings or shoes will soon require attention.

In some cases it may not be desirable to permit axial movement of the brake operating lever. may be slightly modified by (lispensing with the spring a in the recess in thcyoperating lever n and instead of fixing the member Z: to the actuating shaft, it may be slidably keyed thereto. Figures 3 and 4; show the construction of the member 70 when two keys are adopted but it will be readily understood that castellations squares, hexagons or the like. may be used, one of said keys being shown in dotted lines at 0 in Figure 2. ln this case the action is substantially the same, with the exception that In this case the construction memos the member 7a is slidden axially against the action of the spring m when the teeth 12) of the ratchet of operatin lever it slide freely past the ratchet teeth 0 the member is.

The operating lever n and the ring or sleeve 9 keyed to the brake casing may be provided with annular projecting rims n and g respectively serving to receive the ends of a flexible leather or other protective casing (not shown) which may be secured over these rims and may serve to retain grease or other lubricant and also exclude dust and. water and thus ensure correct operating of the mechanism.

I claim:

1. Operating m chanism for brakes, comprising an operating shaft, an operating member loosely mounted on said shaft, teeth on said operating member, a drivingclutch mounted in driving relation with said shaft and having teeth to co operate with the teeth on the operating member, projections on said driving clutch, a loose clutch mounted on said shaft and having recesses co-operating with the projections on the driving clutch, and means for preventing said loose clutch from rotating backwardly on said shaft.

2. Operating mechanismfor brakes, comprising an operating shaft, an 'operating member loosely mounted on said shaft, teeth on said operating member, a driving clutch mounted in driving relation with said shaft and having teeth tol co-operate with the teeth on the operating member, projections on said driving clutch, a loose clutchmounted'on said shaft and having recesses cooperating with the projections onthe driving clutch, a clearance between said projections and recesses sufiicient topermit of a reason- 'able clearance between the brake shoe and drum, and means for preventing said loose clutch from rotating backwardly on said shaft 3. Operating mechanism for brakes, comprising an operating shaft, an operating member loosely mounted on said shaft, teet on said operating member, a driving clutch mounted in driving relation with said shaft and having teeth to co-operate with the teeth on the operating member, projections on said driving clutch, a loose clutch mounted on said shaft, for rotation in one direction only, said loose clutch having recesses co-operatlng 'with'the projections on the driving clutch, and means for preventing said loose clutch from rotating backwardly on said shaft.

4. Operating mechanism. for brakes, comprising an operating shaft, an operatlng member loosely mounted on said shaft,

teeth on said operating member, a driving clutch mounted in driving relationwith said shaft, and having teeth to 00-0 erate with the teeth on the operating mem er, pro ections on said driving clutch, a loose clutch with said shaft and having oppositel mounted on said shaft, for rotation in one direction only, said loose. clutch'having recesses co-operating with the projections on the driving clutch, a clearance between said projections and recesses sufficient to permit of a reasonable clearance between the brake shaft, and a lever associated with-said shaft v for indicating the wear on the brake shoe.

6. Operating mechanism for brakes, comprising an operating shaft, an operating member loosely mounted on said shaft,

ratchet teeth on said operating member, a,

driving clutch mounted in driving relation disposedratchet teeth to. co-operate wit the teeth on the operating member, projections on said driving clutch, a loose clutch mounted on said shaft and having recesses cooperating with the projections on the driving'clutch, ratchet teeth for preventing said loose clutch from rotating backwardly on said shaft, and springs tending to keep said teeth in engagement.

I 7. Operating mechanism for brakes, comprising an operating shaft, an operating member loosely mounted on said shaft, ratchet'teeth on said operating member, a driving clutch mounted in driving relation with said shaft and havingoppositely disposed ratchet teeth to co-operate with the teeth on the operating member, projections on said driving clutch, a loose clutch mounted on said shaft, recesses in said loose clutch co-operating with the projections on -the driving clutch, a clearance between said projections and recesses sufficient to permit of a reasonable clearance between the brake shoe and drum, ratchet teeth for preventing said loose clutch from rotating backwardly on said shaft, and springs tending'to keep said teeth in engagement. 8. Operating mechanism for brakes comprising an operating shaft, an operating member loosely mounted on said shaft, ratchet teeth on said operating member, a driving clutch mountedin driving relation with said shaft and having oppositely disposed ratchet teeth to cooperate with the teeth on the operating member projections on said driving clutch, a loose cf itch mount its ed on said shaft for rotation in one direction only, said loose clutch having recesses 00- operating with the projections on the driving clutch, a clearance between said projections and recesses sufficient to permit of a reasonable clearance between the brake shoe and drum, ratchet teeth for preventing said loose clutch from rotating backwardly on said shaft, springs tending to keep said teeth in engagement and a lever associated with 10 said shaft for indicating the Wear on the brake shoe.

WILLIAM RGEEIERT RYIDE HlSCU'R'T. 

